Re: Random panic in load_balance() with 3.16-rc

2014-08-04 Thread Steven Rostedt
On Fri, 25 Jul 2014 11:29:06 -0700 Linus Torvalds wrote: > On Fri, Jul 25, 2014 at 7:02 AM, Steven Rostedt wrote: > > > > But wouldn't it be rather trivial to run a static analyzer on the final > > vmlinux to make sure there are no red zones? I mean, you would

Re: Random panic in load_balance() with 3.16-rc

2014-07-25 Thread Steven Rostedt
On Fri, 25 Jul 2014 13:01:11 -0700 Linus Torvalds wrote: > For example, gcc will not create a small stack frame with "sub > $8,%rsp". No, what gcc does is to use a random "push" instruction. > Fair enough, but that really makes things much harder to see. Here's > an example: > > 81314

Re: Random panic in load_balance() with 3.16-rc

2014-07-25 Thread Steven Rostedt
On Fri, 25 Jul 2014 11:29:06 -0700 Linus Torvalds wrote: > On Fri, Jul 25, 2014 at 7:02 AM, Steven Rostedt wrote: > > > > But wouldn't it be rather trivial to run a static analyzer on the final > > vmlinux to make sure there are no red zones? I mean, you would

Re: Random panic in load_balance() with 3.16-rc

2014-07-25 Thread Steven Rostedt
On Thu, Jul 24, 2014 at 08:55:28PM -0700, Alexei Starovoitov wrote: > > -mno-red-zone only affected prologue emition in gcc. This part didn't > change between the releases. So the bug is quite deep. > What seems to be happening is that 2nd pass of instruction scheduler > (after emit prologue and r